DE1717152A1 - Method of making a catalyst - Google Patents

Description

Daido Steel Company, Ltd., and

Okaya & Co., Ltd.

2 June 3, 1970

Process for the preparation of a catalyst

The present invention relates to a process for the preparation of a catalyst, and particularly one of very fine grain size, which is excellent in desulfurization and combustion efficiency.

Various methods of manufacturing metal powder have been proposed, but none capable of producing fine grains with a uniform grain size of up to 1 / U. However, if it is possible to produce such a very fine and uniform grain material or to settle on a support or knock down, the utility of the catalyst can be increased and consequently an improvement in industrial performance achieved. The method according to the invention allows the production of a powder from a metal, a metal alloy, a metal oxide or metal sulfide with a surprisingly fine grain diameter of the order of magnitude of 5000-50 Å and a good grain size distribution. Such catalysts can be used with very high efficiency for burning and removing certain toxic components from exhaust gases and for desulphurising various hydrocarbon oils.

109882/1774

Documents (Art 7 | 1 AM. 2 No. J Satt 3 dw Amendment *** v. 4.9.1 WH

To achieve these advantages, the invention consists firstly in the selection of a raw material or starting material for one Catalyst with very high efficiency in the fields of application mentioned above and, secondly, in the creation a method of improving the catalytic activity by converting the grain size of this catalyst into a Area of very fine diameter, on the order of a few angstrom units. Finally, the invention is concerned nor to provide a process for producing an excellent catalyst for desulfurization and combustion.

The catalyst according to the invention made of nickel, cobalt, molybdenum, vanadium, platinum, palladium, chromium or titanium, an alloy of these metals, such as nickel-chromium, iron-nickel, cobalt-iron, cobalt-molybdenum or nickel-vanadium, or a The compound of these metals, such as AlgCU, V ₃ O ^, Fe ₂ O ₃ , NiS, MoS, is characterized in that its catalyst particles have a grain diameter of about 50 to 5000%. The process according to the invention for producing this catalyst is characterized in that the catalyst material is evaporated at an ambient gas pressure between about 0.1 and 300 Torr and then precipitated and that a low gas pressure for the production of catalyst particles with a small particle diameter and for the production of catalyst particles with a large particle diameter a higher gas pressure is used.

It is also possible to provide a carrier and to deposit the material on it in order to have the catalyst at the same time to connect with the carrier, but the latter does not necessarily need to be in the one under reduced pressure Chamber to be made.

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All metals of the Periodic Table of the Elements, for example Ni, Co, Mo, V, Pt, Pd, Cr and Ti, as well as metal alloys or compounds such as metal oxides or sulfides, can be used as metallic substances with catalytic effectiveness, for example Ni Cr, Fe-Ni, Co-Fe, Co-Mo, Ni-V, Al ₂ O ₃ , V ₃ O ₃ , Fe ₃ O ₃ , NiS and MoS.

Preferably, in the above-mentioned reduced pressure chamber for heating, vaporizing and solidifying of the material possessing catalytic activity, preferably an inert atmosphere prevails. Therefor argon, nitrogen and hydrogen are available. Pure oxygen is used in the production of oxides, in the production of sulfides hydrogen sulfide and in the case of the production of nitrides, gaseous ammonia, while, for example, in the case of the production of a compound a special protective atmosphere gas is used.

As a carrier on which in its catalytic effectiveness As improved granular material is deposited or deposited, an iron group metal such as nickel or Cobalt, or an alloy of elements of this group, is used, for example stainless steel because of its high mechanical strength and its corrosion resistance is preferred.

Of course, with the exception of metals with a low melting point and poor corrosion resistance, one can too use any other metals than those mentioned. The catalyst becomes a strip grid, a honeycomb or Wire mesh formed and then commonly used as an object made up of a combination of a mesh shape thin, twisted together with relaxed twists

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Consists of metal strips. If the catalyst is used for special purposes, however, it can also consist of a lattice-shaped metal wire or a metal mesh. The carrier preferably has the largest possible contact surface and can be made of silicon, aluminum or zirconium oxide to beat. Palis did not use such a carrier can be replaced by another carrier.

Since the bond between the metal grain of the catalyst and the support is of a physical nature and of considerable Is strength, the catalyst can be used satisfactorily without further treatment. However, if necessary, the deposition of the metal granules can occur be strengthened to the carrier by sintering or a similar additional process. In addition, the Control the grain diameter of the fine metal grains according to the required deposit condition.

As a heat source for the heating mentioned, plasma, plasma beam, electron beam, electrically heated Tungsten, arc or laser arrangements can be used. When using a heat source generating ultra-high temperatures, such as a plasma beam or a laser arrangement, a metal or a metal compound, such as a Metal oxide or sulfide, to one above the boiling point lying temperature heated. When heated in this way, said material is atomized or vaporized, see above that very fine particles with a narrow distribution range and high uniformity of grain size are obtained. Sine The grain size can be divided by controlling the pressure the protective atmosphere can be achieved; at a pressure of 1 mm Hg, the grain size is generally uniform

109882/1774

100 S, while at a pressure of 300 mm Hg Grain sizes in the range of 1000 pounds can be achieved. The higher the pressure, the larger the grain size and vice versa.

However, if the pressure is less than 10 ~ mm Hg, the evaporated material adheres to the inner wall of the device in the form of a vaporized film, eo that no particulate powder body can be produced. On the other hand, if a pressure close to atmospheric pressure is used, it will be dea when heated Materials difficult to reach vapor pressure in terms of vapor pressure. Since also with higher pressure a larger grain diameter is achieved and the catalyst thus loses its effectiveness, the preferred pressure range is between 10 and 300 mm Hg.

The invention is described in more detail below using exemplary embodiments:

example 1

Manufacture of a nickel catalyst nickel is heated on an electrically heated tungsten base at a pressure of 50 mm Hg in a protective argon atmosphere to about 3000 ⁰ O until it evaporates, so that a fine powder with a grain size of 300-450 S and uniformly high purity is accumulated in a precipitate without secondary aggregation. The grain size distribution is in a very narrow range below 450 Å and averages 350 Å. In contrast, the grain size that can be achieved with a conventional oxidation reduction process is at least about 1000 S and has a very wide distribution spectrum.

9982/1774

Example 2

Manufacture of a platinum catalyst : strips of stainless steel with a width of 2 mm and 0.15 mm in thickness are twisted together for the purpose of forming a wire consisting of the strips with a pitch ten times the width of the strip; A five-layer metal mesh is made from this wire. This metal grid is placed in a closed chamber with an argon protective atmosphere under reduced pressure of less than 10 mm Hg, in which platinum is evaporated for the purpose of depositing platinum grains on the metal grid. In this pail, the size of the platinum granules is about 200 Å and the deposit is uniform in thickness of about 1000 %. The apparatus used for this purpose is described in the applicant's Japanese Patent Application No. 38-16068.

Example 3

Desulfurization of the catalyst : The silica catalyst according to Example 1 is mixed with a small amount of alcohol in order to put it in a gel-like state, so that it adheres to AlpO-, (mesh size 30-60 mesh.) And dries on it, whereupon it is examined in a reaction tube is inserted.

A special type of benzene is produced from the sample by adding thiophene, with its S content is adjusted according to the following table to investigate the desulfurization, the following results demonstrate:

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Tabel

Sample desulfurization conditions

result

($> S im Reakti- throughput amount Katalyaa- total amount of S Bntschwe-

gate supply-related

Benzene) onstempe- amount to total speed

in delivery maneuverability

rature

( ⁰ C)

0.1 400 0.1 400 0.1 400

HO HO HO

^C 6 ^H 6

6.0 6.0 6.0

Ni
(G) (G) ' ³ benzene
(cm ³ ) ge of benzene 4.0 8th, O approximately
20th approximately
0.02 4.0 8th, O approximately
20th approximately
0.02 4.0 8th, O approximately
20th approximately
0.02

73 90

Example 4

Use of the combustion catalyst i The product prepared according to Example 2 is used as a combustion catalyst for purifying gas used for burning enameled wire. This catalyst is placed in a cyclic gas path for gas used in burning enamel wire, with good results. If no catalyst is used, a tar-like substance is deposited in the flow channel of the exhaust gases, whereas no tar-like substance is found when using the catalyst according to the invention. Accordingly, good results are achieved at an exhaust gas temperature of 200.degree. C., whereas these results are only achieved after the exhaust gases are reheated to 250.degree. C. when the conventional catalyst is used.

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Although the above examples represent typical embodiments of the invention, the composition can and the form of the catalyst is of course arbitrary within the scope of the invention depending on the intended use be modified.

For the desulfurization of hydrocarbon oil with the aid of the catalyst according to the invention, known suspension, Flotation and fixed bed processes are used. Wherever unburned carbon monoxide can be found in the exhaust gases of motor vehicles as well as in the combustion gas of oil stoves finds additives or aldehydes with very unpleasant Odor, as in the plastic, dye and varnish, painting supplies and rubber industry, or exhaust gases with fumes generated from organic sulfur compound, can help eliminate the hygienic hazards of such exhaust gases, the combustion catalyst according to the invention can be used to a large extent, its efficiency is very high due to the excellent effectiveness of its ultra-fine grain structure.

109882/1774

Claims (8)

Claims 1. Fine-grained catalyst made of nickel, cobalt, molybdenum, vanadium, platinum, palladium, chromium or titanium, an alloy of these metals, such as nickel-chromium, bis-nickel, cobalt-bis-iron, cobalt-molybdenum or nickel-vanadium , or a compound of these metals, such as AIpCU, Vp ^ V ^ ^e 2 ^ V NiS, MoS, characterized in that its catalyst particles have a grain diameter of about 50 to 5000 S. 2. A method for producing a catalyst according to claim 1, characterized in that the catalyst material evaporated at an ambient gas pressure between about 0.1 and 300 torr and then precipitated and that for the production of catalyst particles with a small grain diameter, a low gas pressure and a higher gas pressure is used to produce catalyst particles with a large grain diameter. 3. The method according to claim 1 or 2, characterized in that the catalytic effectiveness improving, very fine-grained material with a grain diameter of 50 5000 Å deposited or deposited on a carrier will. 4. The method according to claim 1 to 3> characterized in that the catalytic effectiveness possessing starting material of any metal of the Periodic Table of the Elements, such as Ni, Co, χ, ίο, V, Pt, Pd, Cr or Ti, an alloy of these Metals such as K ^r i-Cr, - 10 New lower eyelid ft # ΆΜ & ΪΑ Sentence ^ X,. »Una« ** ■ *. *. X mn BASS ORIGINAL - ίο - Pe-Ni, Co-Fe, Co-Mo or Ni-Y, or a compound of these metals, such as Al ₂ O, V ₂ O ₃ , Fe ₂ O ₃ , NiS or MoS and the like. 5. The method according to the preceding claims, characterized in that the in the under reduced pressure standing chamber in which the starting material having catalytic activity is heated, evaporated and solidified, the atmosphere is an inert gas such as argon, nitrogen or hydrogen, or a gas compound such as hydrogen sulfide and carbon monoxide, Oxygen, ammonia and chlorine, is. 6. The method according to claim 3, characterized in that the deposition of the very fine-grained material which improves the catalytic effectiveness is made on a carrier outside the chamber under reduced pressure in which the Granular material is produced. 7. The method according to claim 3 »characterized in that the depositing or depositing of the catalytic effectiveness improving, very fine-grained material on a in the chamber under reduced pressure in which the granular material is produced, introduced carrier simultaneously with the production of the material is made . 8. The method according to claim 2, characterized in that the carrier is a metal strip grid, a metal strip honeycomb structure, a metal wire mesh or a non-metallic carrier such as aluminum or silicon oxide. 1 U 9 ;;;; ) J ι 7? :. , y < ^f BATH ORIGINAL